As network traffic demands increase, new transmission devices, e.g., transceivers, transponders, and transmission modules, are required to support higher data transfer rates, e.g., 40 Gbps and 100 Gbps. Accordingly, new test devices are needed for validation and testing of these transmission devices.
Transmission devices supporting higher data transfer rates have been developed in compliance with various standards defined by multiple source agreements (MSAs). For example, the C form factor pluggable (CFP) MSA defines CFP, CFP2, and CFP4 standards for hot-pluggable optical transceivers supporting data transfer rates of 40 Gbps and 100 Gbps. Documents relating to the CFP MSA include the “CFP MSA Hardware Specification”, Revision 1.4, Jun. 7, 2010, the “CFP MSA CFP2 Hardware Specification”, Revision 1.0, Jul. 31, 2013, and the “CFP MSA Management Interface Specification”, Version 2.0 r09, Apr. 10, 2012, and Version 2.2 r06a, Jul. 31, 2013, all of which are incorporated herein by reference. The Optical Internetworking Forum (OIF) MSA for a 100 Gbps long-haul (100 GLH) transmission module defines an OIF-MSA-100 GLH standard for board-mounted optical transmission modules supporting a data transfer rate of 100 Gbps. Documents relating to the OIF-MSA-100 GLH include “Implementation Agreement for 100 G Long-Haul DWDM Transmission Module—Electromechanical (MSA-100 GLH)”, Revision 1.1, Sep. 20, 2011, which is incorporated herein by reference.
All of the CFP, CFP2, CFP4, and OIF-MSA-100 GLH standards specify the use of the management data input/output (MDIO) interface, as defined in Clause 45 of the “IEEE Standard for Ethernet”, IEEE Std 802.3-2012, Dec. 28, 2012, which is incorporated herein by reference. These standards also specify the use of similar sets of non-MDIO control signals, i.e., direct control signals.
With reference to FIG. 1, a conventional test device 100 for testing such transmission devices does not provide direct control of a transmission device as a device under test (DUT) 150. The conventional test device 100 includes a test interface 110 and a remote control interface 120. However, the conventional test device 100 does not include an integrated control interface for directly controlling the DUT 150 via MDIO and non-MDIO control signals. Rather, the DUT 150 is indirectly controlled by an external control device 160.
In the test setup of FIG. 1, the remote control interface 120 of the test device 100 is coupled to the external control device 160, e.g., a computer running control software, and the test interface 110 of the test device 100 is coupled to a data interface 151 of the DUT 150. The external control device 160 has control over the control plane. The external control device 160 is coupled to a conversion device 170, which is coupled to a control interface 152 of the DUT 150. The conversion device 170 is required to convert control signals, e.g., universal serial bus (USB) signals, provided by the external control device 160 to MDIO and non-MDIO control signals supported by the DUT 150.
Unfortunately, in the test setup of FIG. 1, it is difficult to synchronize control transactions between the external control device 160 and control interface 152 of the DUT 150 with test data transactions between the test interface 110 of the test device 100 and data interface 151 of the DUT 150. Synchronization is possible with limited precision only and, usually, requires running complex real-time control software on the external control device 160. It is also difficult to correlate test results obtained by the test interface 110 of the test device 100 with status information about the DUT 150 obtained by the external control device 160, because the timing of test events is only precisely known within the test device 100.
Therefore, an improved test device and method are desirable.